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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-03-06 13:17:21 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-03-06 13:17:21 +0100
commit34ff6c2fe366f389dbe45badb5d100bd3aa02bea (patch)
tree4d5086eba6117b53f0397ccee9a31851cabeb4e5 /drivers/iio/adc
parentcc4e33d961276bd2e72add5188a124f51c11801d (diff)
parent2df79e1bddc46ea6ce9746a171220c3f68e378da (diff)
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Merge tag 'iio-for-4.12a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes: First set of IIO new device support, features and cleanup for the 4.12 cycle. Quite a bit of outreachy activity here with a driver from a current intern and a number of cleanup patches as part of the next round. Getting a pull request in early this cycle as it's looking like another large cycle for IIO. New device support * adxl345 - initial device support. Note, once complete support is done the intent is to superceded the driver in input/misc. - bindings. - conversion from i2c direct calls to regmap and driver split. - spi support. * chromeos light and proximity. - new driver. * devantech srf04 ultrasonic ranger - new driver with device tree bindings. * hid temperature - new driver for environemntal temperature support from hid devices. * max30102 oximeter - new driver with device tree bindings. * st lsm6dsx - refactor and addition of device support for lsm6dsl and lsm6ds3h. Staging graduation * isl29028 including copyright notice update to reflect Brian's work. * lpc32xx_adc. * spear adc. It's not perfect and there are some datasheet disagreements, but it works and is good enough to graduate. New features * documentation - abi docs for in_proximity_sampling_frequency_available. - generalise counting direction ABI docs as a second driver is going to use them. * hid-sensor-prox - Add support for HID_USAGE_SENSOR_HUMAN_PRESENCE if used on a particular device. * isl29028 - runtime pm. * meson-saradc - switch from polling to interrupt mode and improved read_raw_sample function to avoid unnecessary loop. * tmp007 - interrupt and threshold event support. Cleanups and minor fixes * ad2s1210 - permissions to octal. * ad7192 - permissions to octal. - use BIT macro. * ad9832 - merge header definitions into source file. * ad9834 - merge header definitions into source file. * ade7753 - merge header definitions into source file. - cleanup include ordering. * ade7854 - simplify return logic. * adis16201 - merge header definitions into source file. - rename _core.c to .c as there is nothing else. * adis16203 - merge header definitions into source file. - rename _core.c to .c as there is nothing else. * adis16209 - merge header definitions into source file. - rename _core.c to .c as there is nothing else. * adis16240 - permissions to octal. - merge header definitions into source file. - rename _core.c to .c as there is nothing else. * adt7136 - permissions to octal. * cio-dac - set missing parent device. * documentation - update version numbers on sysfs ABI for counter bits that didn't quite. make 4.9. * isl29028 - mdelay to msleep. - incorrrect sleep time when taking first proximity reading. * lmp91000 - set missing parent device. * lpc32xx - Consistent prefixes for defines. - rename local state structure to _state. * max30100 - set missing parent device. * max30102 - set missing parent device. * maxim-thermocouple - set missing parent device. * meter driver header - permissions to octal. * pulsedlight-lidar-lite-v2 - set missing parent device. * quad-8 - set missing parent device. * st104 - set missing parent device. Other * Mailmap - update Matt Ranostay's email address to the Konsolko one.
Diffstat (limited to 'drivers/iio/adc')
-rw-r--r--drivers/iio/adc/Kconfig23
-rw-r--r--drivers/iio/adc/Makefile2
-rw-r--r--drivers/iio/adc/lpc32xx_adc.c219
-rw-r--r--drivers/iio/adc/meson_saradc.c90
-rw-r--r--drivers/iio/adc/spear_adc.c395
-rw-r--r--drivers/iio/adc/stx104.c1
6 files changed, 707 insertions, 23 deletions
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index dedae7adbce9..d777a972586d 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -305,6 +305,18 @@ config LPC18XX_ADC
To compile this driver as a module, choose M here: the module will be
called lpc18xx_adc.
+config LPC32XX_ADC
+ tristate "NXP LPC32XX ADC"
+ depends on ARCH_LPC32XX || COMPILE_TEST
+ depends on HAS_IOMEM
+ help
+ Say yes here to build support for the integrated ADC inside the
+ LPC32XX SoC. Note that this feature uses the same hardware as the
+ touchscreen driver, so you should either select only one of the two
+ drivers (lpc32xx_adc or lpc32xx_ts) or, in the OpenFirmware case,
+ activate only one via device tree selection. Provides direct access
+ via sysfs.
+
config LTC2485
tristate "Linear Technology LTC2485 ADC driver"
depends on I2C
@@ -494,6 +506,17 @@ config ROCKCHIP_SARADC
To compile this driver as a module, choose M here: the
module will be called rockchip_saradc.
+config SPEAR_ADC
+ tristate "ST SPEAr ADC"
+ depends on PLAT_SPEAR || COMPILE_TEST
+ depends on HAS_IOMEM
+ help
+ Say yes here to build support for the integrated ADC inside the
+ ST SPEAr SoC. Provides direct access via sysfs.
+
+ To compile this driver as a module, choose M here: the
+ module will be called spear_adc.
+
config STM32_ADC_CORE
tristate "STMicroelectronics STM32 adc core"
depends on ARCH_STM32 || COMPILE_TEST
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index d0012620cd1c..b11bb5767543 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -30,6 +30,7 @@ obj-$(CONFIG_IMX7D_ADC) += imx7d_adc.o
obj-$(CONFIG_INA2XX_ADC) += ina2xx-adc.o
obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
obj-$(CONFIG_LPC18XX_ADC) += lpc18xx_adc.o
+obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o
obj-$(CONFIG_LTC2485) += ltc2485.o
obj-$(CONFIG_MAX1027) += max1027.o
obj-$(CONFIG_MAX11100) += max11100.o
@@ -46,6 +47,7 @@ obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o
obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o
obj-$(CONFIG_RCAR_GYRO_ADC) += rcar-gyroadc.o
obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o
+obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
obj-$(CONFIG_STX104) += stx104.o
obj-$(CONFIG_STM32_ADC_CORE) += stm32-adc-core.o
obj-$(CONFIG_STM32_ADC) += stm32-adc.o
diff --git a/drivers/iio/adc/lpc32xx_adc.c b/drivers/iio/adc/lpc32xx_adc.c
new file mode 100644
index 000000000000..0de709b4288b
--- /dev/null
+++ b/drivers/iio/adc/lpc32xx_adc.c
@@ -0,0 +1,219 @@
+/*
+ * lpc32xx_adc.c - Support for ADC in LPC32XX
+ *
+ * 3-channel, 10-bit ADC
+ *
+ * Copyright (C) 2011, 2012 Roland Stigge <stigge@antcom.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/completion.h>
+#include <linux/of.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+/*
+ * LPC32XX registers definitions
+ */
+#define LPC32XXAD_SELECT(x) ((x) + 0x04)
+#define LPC32XXAD_CTRL(x) ((x) + 0x08)
+#define LPC32XXAD_VALUE(x) ((x) + 0x48)
+
+/* Bit definitions for LPC32XXAD_SELECT: */
+/* constant, always write this value! */
+#define LPC32XXAD_REFm 0x00000200
+/* constant, always write this value! */
+#define LPC32XXAD_REFp 0x00000080
+ /* multiple of this is the channel number: 0, 1, 2 */
+#define LPC32XXAD_IN 0x00000010
+/* constant, always write this value! */
+#define LPC32XXAD_INTERNAL 0x00000004
+
+/* Bit definitions for LPC32XXAD_CTRL: */
+#define LPC32XXAD_STROBE 0x00000002
+#define LPC32XXAD_PDN_CTRL 0x00000004
+
+/* Bit definitions for LPC32XXAD_VALUE: */
+#define LPC32XXAD_VALUE_MASK 0x000003FF
+
+#define LPC32XXAD_NAME "lpc32xx-adc"
+
+struct lpc32xx_adc_state {
+ void __iomem *adc_base;
+ struct clk *clk;
+ struct completion completion;
+
+ u32 value;
+};
+
+static int lpc32xx_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long mask)
+{
+ struct lpc32xx_adc_state *st = iio_priv(indio_dev);
+
+ if (mask == IIO_CHAN_INFO_RAW) {
+ mutex_lock(&indio_dev->mlock);
+ clk_prepare_enable(st->clk);
+ /* Measurement setup */
+ __raw_writel(LPC32XXAD_INTERNAL | (chan->address) |
+ LPC32XXAD_REFp | LPC32XXAD_REFm,
+ LPC32XXAD_SELECT(st->adc_base));
+ /* Trigger conversion */
+ __raw_writel(LPC32XXAD_PDN_CTRL | LPC32XXAD_STROBE,
+ LPC32XXAD_CTRL(st->adc_base));
+ wait_for_completion(&st->completion); /* set by ISR */
+ clk_disable_unprepare(st->clk);
+ *val = st->value;
+ mutex_unlock(&indio_dev->mlock);
+
+ return IIO_VAL_INT;
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_info lpc32xx_adc_iio_info = {
+ .read_raw = &lpc32xx_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+#define LPC32XX_ADC_CHANNEL(_index) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = _index, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .address = LPC32XXAD_IN * _index, \
+ .scan_index = _index, \
+}
+
+static const struct iio_chan_spec lpc32xx_adc_iio_channels[] = {
+ LPC32XX_ADC_CHANNEL(0),
+ LPC32XX_ADC_CHANNEL(1),
+ LPC32XX_ADC_CHANNEL(2),
+};
+
+static irqreturn_t lpc32xx_adc_isr(int irq, void *dev_id)
+{
+ struct lpc32xx_adc_state *st = dev_id;
+
+ /* Read value and clear irq */
+ st->value = __raw_readl(LPC32XXAD_VALUE(st->adc_base)) &
+ LPC32XXAD_VALUE_MASK;
+ complete(&st->completion);
+
+ return IRQ_HANDLED;
+}
+
+static int lpc32xx_adc_probe(struct platform_device *pdev)
+{
+ struct lpc32xx_adc_state *st = NULL;
+ struct resource *res;
+ int retval = -ENODEV;
+ struct iio_dev *iodev = NULL;
+ int irq;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "failed to get platform I/O memory\n");
+ return -ENXIO;
+ }
+
+ iodev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
+ if (!iodev)
+ return -ENOMEM;
+
+ st = iio_priv(iodev);
+
+ st->adc_base = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (!st->adc_base) {
+ dev_err(&pdev->dev, "failed mapping memory\n");
+ return -EBUSY;
+ }
+
+ st->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(st->clk)) {
+ dev_err(&pdev->dev, "failed getting clock\n");
+ return PTR_ERR(st->clk);
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq <= 0) {
+ dev_err(&pdev->dev, "failed getting interrupt resource\n");
+ return -ENXIO;
+ }
+
+ retval = devm_request_irq(&pdev->dev, irq, lpc32xx_adc_isr, 0,
+ LPC32XXAD_NAME, st);
+ if (retval < 0) {
+ dev_err(&pdev->dev, "failed requesting interrupt\n");
+ return retval;
+ }
+
+ platform_set_drvdata(pdev, iodev);
+
+ init_completion(&st->completion);
+
+ iodev->name = LPC32XXAD_NAME;
+ iodev->dev.parent = &pdev->dev;
+ iodev->info = &lpc32xx_adc_iio_info;
+ iodev->modes = INDIO_DIRECT_MODE;
+ iodev->channels = lpc32xx_adc_iio_channels;
+ iodev->num_channels = ARRAY_SIZE(lpc32xx_adc_iio_channels);
+
+ retval = devm_iio_device_register(&pdev->dev, iodev);
+ if (retval)
+ return retval;
+
+ dev_info(&pdev->dev, "LPC32XX ADC driver loaded, IRQ %d\n", irq);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id lpc32xx_adc_match[] = {
+ { .compatible = "nxp,lpc3220-adc" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, lpc32xx_adc_match);
+#endif
+
+static struct platform_driver lpc32xx_adc_driver = {
+ .probe = lpc32xx_adc_probe,
+ .driver = {
+ .name = LPC32XXAD_NAME,
+ .of_match_table = of_match_ptr(lpc32xx_adc_match),
+ },
+};
+
+module_platform_driver(lpc32xx_adc_driver);
+
+MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
+MODULE_DESCRIPTION("LPC32XX ADC driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c
index 89def6034f40..cde9ca7a01b8 100644
--- a/drivers/iio/adc/meson_saradc.c
+++ b/drivers/iio/adc/meson_saradc.c
@@ -18,7 +18,9 @@
#include <linux/io.h>
#include <linux/iio/iio.h>
#include <linux/module.h>
+#include <linux/interrupt.h>
#include <linux/of.h>
+#include <linux/of_irq.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
@@ -163,6 +165,7 @@
#define MESON_SAR_ADC_REG13_12BIT_CALIBRATION_MASK GENMASK(13, 8)
#define MESON_SAR_ADC_MAX_FIFO_SIZE 32
+#define MESON_SAR_ADC_TIMEOUT 100 /* ms */
#define MESON_SAR_ADC_CHAN(_chan) { \
.type = IIO_VOLTAGE, \
@@ -229,6 +232,7 @@ struct meson_sar_adc_priv {
struct clk_gate clk_gate;
struct clk *adc_div_clk;
struct clk_divider clk_div;
+ struct completion done;
};
static const struct regmap_config meson_sar_adc_regmap_config = {
@@ -274,33 +278,31 @@ static int meson_sar_adc_read_raw_sample(struct iio_dev *indio_dev,
int *val)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
- int ret, regval, fifo_chan, fifo_val, sum = 0, count = 0;
+ int regval, fifo_chan, fifo_val, count;
- ret = meson_sar_adc_wait_busy_clear(indio_dev);
- if (ret)
- return ret;
-
- while (meson_sar_adc_get_fifo_count(indio_dev) > 0 &&
- count < MESON_SAR_ADC_MAX_FIFO_SIZE) {
- regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &regval);
-
- fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK,
- regval);
- if (fifo_chan != chan->channel)
- continue;
-
- fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK,
- regval);
- fifo_val &= (BIT(priv->data->resolution) - 1);
+ if(!wait_for_completion_timeout(&priv->done,
+ msecs_to_jiffies(MESON_SAR_ADC_TIMEOUT)))
+ return -ETIMEDOUT;
- sum += fifo_val;
- count++;
+ count = meson_sar_adc_get_fifo_count(indio_dev);
+ if (count != 1) {
+ dev_err(&indio_dev->dev,
+ "ADC FIFO has %d element(s) instead of one\n", count);
+ return -EINVAL;
}
- if (!count)
- return -ENOENT;
+ regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &regval);
+ fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval);
+ if (fifo_chan != chan->channel) {
+ dev_err(&indio_dev->dev,
+ "ADC FIFO entry belongs to channel %d instead of %d\n",
+ fifo_chan, chan->channel);
+ return -EINVAL;
+ }
- *val = sum / count;
+ fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval);
+ fifo_val &= GENMASK(priv->data->resolution - 1, 0);
+ *val = fifo_val;
return 0;
}
@@ -378,6 +380,12 @@ static void meson_sar_adc_start_sample_engine(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ reinit_completion(&priv->done);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_FIFO_IRQ_EN,
+ MESON_SAR_ADC_REG0_FIFO_IRQ_EN);
+
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE,
MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE);
@@ -392,6 +400,9 @@ static void meson_sar_adc_stop_sample_engine(struct iio_dev *indio_dev)
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 0);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLING_STOP,
MESON_SAR_ADC_REG0_SAMPLING_STOP);
@@ -643,6 +654,7 @@ static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
int ret;
+ u32 regval;
ret = meson_sar_adc_lock(indio_dev);
if (ret)
@@ -667,6 +679,9 @@ static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
goto err_sana_clk;
}
+ regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
MESON_SAR_ADC_REG11_BANDGAP_EN,
MESON_SAR_ADC_REG11_BANDGAP_EN);
@@ -728,6 +743,25 @@ static int meson_sar_adc_hw_disable(struct iio_dev *indio_dev)
return 0;
}
+static irqreturn_t meson_sar_adc_irq(int irq, void *data)
+{
+ struct iio_dev *indio_dev = data;
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ unsigned int cnt, threshold;
+ u32 regval;
+
+ regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
+ cnt = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
+ threshold = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
+
+ if (cnt < threshold)
+ return IRQ_NONE;
+
+ complete(&priv->done);
+
+ return IRQ_HANDLED;
+}
+
static const struct iio_info meson_sar_adc_iio_info = {
.read_raw = meson_sar_adc_iio_info_read_raw,
.driver_module = THIS_MODULE,
@@ -770,7 +804,7 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
struct resource *res;
void __iomem *base;
const struct of_device_id *match;
- int ret;
+ int irq, ret;
indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv));
if (!indio_dev) {
@@ -779,6 +813,7 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
}
priv = iio_priv(indio_dev);
+ init_completion(&priv->done);
match = of_match_device(meson_sar_adc_of_match, &pdev->dev);
priv->data = match->data;
@@ -797,6 +832,15 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
if (IS_ERR(base))
return PTR_ERR(base);
+ irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
+ if (!irq)
+ return -EINVAL;
+
+ ret = devm_request_irq(&pdev->dev, irq, meson_sar_adc_irq, IRQF_SHARED,
+ dev_name(&pdev->dev), indio_dev);
+ if (ret)
+ return ret;
+
priv->regmap = devm_regmap_init_mmio(&pdev->dev, base,
&meson_sar_adc_regmap_config);
if (IS_ERR(priv->regmap))
diff --git a/drivers/iio/adc/spear_adc.c b/drivers/iio/adc/spear_adc.c
new file mode 100644
index 000000000000..5dd61f6a57b9
--- /dev/null
+++ b/drivers/iio/adc/spear_adc.c
@@ -0,0 +1,395 @@
+/*
+ * ST SPEAr ADC driver
+ *
+ * Copyright 2012 Stefan Roese <sr@denx.de>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/completion.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+/* SPEAR registers definitions */
+#define SPEAR600_ADC_SCAN_RATE_LO(x) ((x) & 0xFFFF)
+#define SPEAR600_ADC_SCAN_RATE_HI(x) (((x) >> 0x10) & 0xFFFF)
+#define SPEAR_ADC_CLK_LOW(x) (((x) & 0xf) << 0)
+#define SPEAR_ADC_CLK_HIGH(x) (((x) & 0xf) << 4)
+
+/* Bit definitions for SPEAR_ADC_STATUS */
+#define SPEAR_ADC_STATUS_START_CONVERSION BIT(0)
+#define SPEAR_ADC_STATUS_CHANNEL_NUM(x) ((x) << 1)
+#define SPEAR_ADC_STATUS_ADC_ENABLE BIT(4)
+#define SPEAR_ADC_STATUS_AVG_SAMPLE(x) ((x) << 5)
+#define SPEAR_ADC_STATUS_VREF_INTERNAL BIT(9)
+
+#define SPEAR_ADC_DATA_MASK 0x03ff
+#define SPEAR_ADC_DATA_BITS 10
+
+#define SPEAR_ADC_MOD_NAME "spear-adc"
+
+#define SPEAR_ADC_CHANNEL_NUM 8
+
+#define SPEAR_ADC_CLK_MIN 2500000
+#define SPEAR_ADC_CLK_MAX 20000000
+
+struct adc_regs_spear3xx {
+ u32 status;
+ u32 average;
+ u32 scan_rate;
+ u32 clk; /* Not avail for 1340 & 1310 */
+ u32 ch_ctrl[SPEAR_ADC_CHANNEL_NUM];
+ u32 ch_data[SPEAR_ADC_CHANNEL_NUM];
+};
+
+struct chan_data {
+ u32 lsb;
+ u32 msb;
+};
+
+struct adc_regs_spear6xx {
+ u32 status;
+ u32 pad[2];
+ u32 clk;
+ u32 ch_ctrl[SPEAR_ADC_CHANNEL_NUM];
+ struct chan_data ch_data[SPEAR_ADC_CHANNEL_NUM];
+ u32 scan_rate_lo;
+ u32 scan_rate_hi;
+ struct chan_data average;
+};
+
+struct spear_adc_state {
+ struct device_node *np;
+ struct adc_regs_spear3xx __iomem *adc_base_spear3xx;
+ struct adc_regs_spear6xx __iomem *adc_base_spear6xx;
+ struct clk *clk;
+ struct completion completion;
+ u32 current_clk;
+ u32 sampling_freq;
+ u32 avg_samples;
+ u32 vref_external;
+ u32 value;
+};
+
+/*
+ * Functions to access some SPEAr ADC register. Abstracted into
+ * static inline functions, because of different register offsets
+ * on different SoC variants (SPEAr300 vs SPEAr600 etc).
+ */
+static void spear_adc_set_status(struct spear_adc_state *st, u32 val)
+{
+ __raw_writel(val, &st->adc_base_spear6xx->status);
+}
+
+static void spear_adc_set_clk(struct spear_adc_state *st, u32 val)
+{
+ u32 clk_high, clk_low, count;
+ u32 apb_clk = clk_get_rate(st->clk);
+
+ count = DIV_ROUND_UP(apb_clk, val);
+ clk_low = count / 2;
+ clk_high = count - clk_low;
+ st->current_clk = apb_clk / count;
+
+ __raw_writel(SPEAR_ADC_CLK_LOW(clk_low) | SPEAR_ADC_CLK_HIGH(clk_high),
+ &st->adc_base_spear6xx->clk);
+}
+
+static void spear_adc_set_ctrl(struct spear_adc_state *st, int n,
+ u32 val)
+{
+ __raw_writel(val, &st->adc_base_spear6xx->ch_ctrl[n]);
+}
+
+static u32 spear_adc_get_average(struct spear_adc_state *st)
+{
+ if (of_device_is_compatible(st->np, "st,spear600-adc")) {
+ return __raw_readl(&st->adc_base_spear6xx->average.msb) &
+ SPEAR_ADC_DATA_MASK;
+ } else {
+ return __raw_readl(&st->adc_base_spear3xx->average) &
+ SPEAR_ADC_DATA_MASK;
+ }
+}
+
+static void spear_adc_set_scanrate(struct spear_adc_state *st, u32 rate)
+{
+ if (of_device_is_compatible(st->np, "st,spear600-adc")) {
+ __raw_writel(SPEAR600_ADC_SCAN_RATE_LO(rate),
+ &st->adc_base_spear6xx->scan_rate_lo);
+ __raw_writel(SPEAR600_ADC_SCAN_RATE_HI(rate),
+ &st->adc_base_spear6xx->scan_rate_hi);
+ } else {
+ __raw_writel(rate, &st->adc_base_spear3xx->scan_rate);
+ }
+}
+
+static int spear_adc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long mask)
+{
+ struct spear_adc_state *st = iio_priv(indio_dev);
+ u32 status;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&indio_dev->mlock);
+
+ status = SPEAR_ADC_STATUS_CHANNEL_NUM(chan->channel) |
+ SPEAR_ADC_STATUS_AVG_SAMPLE(st->avg_samples) |
+ SPEAR_ADC_STATUS_START_CONVERSION |
+ SPEAR_ADC_STATUS_ADC_ENABLE;
+ if (st->vref_external == 0)
+ status |= SPEAR_ADC_STATUS_VREF_INTERNAL;
+
+ spear_adc_set_status(st, status);
+ wait_for_completion(&st->completion); /* set by ISR */
+ *val = st->value;
+
+ mutex_unlock(&indio_dev->mlock);
+
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_SCALE:
+ *val = st->vref_external;
+ *val2 = SPEAR_ADC_DATA_BITS;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = st->current_clk;
+ return IIO_VAL_INT;
+ }
+
+ return -EINVAL;
+}
+
+static int spear_adc_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ struct spear_adc_state *st = iio_priv(indio_dev);
+ int ret = 0;
+
+ if (mask != IIO_CHAN_INFO_SAMP_FREQ)
+ return -EINVAL;
+
+ mutex_lock(&indio_dev->mlock);
+
+ if ((val < SPEAR_ADC_CLK_MIN) ||
+ (val > SPEAR_ADC_CLK_MAX) ||
+ (val2 != 0)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ spear_adc_set_clk(st, val);
+
+out:
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+}
+
+#define SPEAR_ADC_CHAN(idx) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
+ .channel = idx, \
+}
+
+static const struct iio_chan_spec spear_adc_iio_channels[] = {
+ SPEAR_ADC_CHAN(0),
+ SPEAR_ADC_CHAN(1),
+ SPEAR_ADC_CHAN(2),
+ SPEAR_ADC_CHAN(3),
+ SPEAR_ADC_CHAN(4),
+ SPEAR_ADC_CHAN(5),
+ SPEAR_ADC_CHAN(6),
+ SPEAR_ADC_CHAN(7),
+};
+
+static irqreturn_t spear_adc_isr(int irq, void *dev_id)
+{
+ struct spear_adc_state *st = dev_id;
+
+ /* Read value to clear IRQ */
+ st->value = spear_adc_get_average(st);
+ complete(&st->completion);
+
+ return IRQ_HANDLED;
+}
+
+static int spear_adc_configure(struct spear_adc_state *st)
+{
+ int i;
+
+ /* Reset ADC core */
+ spear_adc_set_status(st, 0);
+ __raw_writel(0, &st->adc_base_spear6xx->clk);
+ for (i = 0; i < 8; i++)
+ spear_adc_set_ctrl(st, i, 0);
+ spear_adc_set_scanrate(st, 0);
+
+ spear_adc_set_clk(st, st->sampling_freq);
+
+ return 0;
+}
+
+static const struct iio_info spear_adc_info = {
+ .read_raw = &spear_adc_read_raw,
+ .write_raw = &spear_adc_write_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static int spear_adc_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device *dev = &pdev->dev;
+ struct spear_adc_state *st;
+ struct resource *res;
+ struct iio_dev *indio_dev = NULL;
+ int ret = -ENODEV;
+ int irq;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(struct spear_adc_state));
+ if (!indio_dev) {
+ dev_err(dev, "failed allocating iio device\n");
+ return -ENOMEM;
+ }
+
+ st = iio_priv(indio_dev);
+ st->np = np;
+
+ /*
+ * SPEAr600 has a different register layout than other SPEAr SoC's
+ * (e.g. SPEAr3xx). Let's provide two register base addresses
+ * to support multi-arch kernels.
+ */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ st->adc_base_spear6xx = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(st->adc_base_spear6xx))
+ return PTR_ERR(st->adc_base_spear6xx);
+
+ st->adc_base_spear3xx =
+ (struct adc_regs_spear3xx __iomem *)st->adc_base_spear6xx;
+
+ st->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(st->clk)) {
+ dev_err(dev, "failed getting clock\n");
+ return PTR_ERR(st->clk);
+ }
+
+ ret = clk_prepare_enable(st->clk);
+ if (ret) {
+ dev_err(dev, "failed enabling clock\n");
+ return ret;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq <= 0) {
+ dev_err(dev, "failed getting interrupt resource\n");
+ ret = -EINVAL;
+ goto errout2;
+ }
+
+ ret = devm_request_irq(dev, irq, spear_adc_isr, 0, SPEAR_ADC_MOD_NAME,
+ st);
+ if (ret < 0) {
+ dev_err(dev, "failed requesting interrupt\n");
+ goto errout2;
+ }
+
+ if (of_property_read_u32(np, "sampling-frequency",
+ &st->sampling_freq)) {
+ dev_err(dev, "sampling-frequency missing in DT\n");
+ ret = -EINVAL;
+ goto errout2;
+ }
+
+ /*
+ * Optional avg_samples defaults to 0, resulting in single data
+ * conversion
+ */
+ of_property_read_u32(np, "average-samples", &st->avg_samples);
+
+ /*
+ * Optional vref_external defaults to 0, resulting in internal vref
+ * selection
+ */
+ of_property_read_u32(np, "vref-external", &st->vref_external);
+
+ spear_adc_configure(st);
+
+ platform_set_drvdata(pdev, indio_dev);
+
+ init_completion(&st->completion);
+
+ indio_dev->name = SPEAR_ADC_MOD_NAME;
+ indio_dev->dev.parent = dev;
+ indio_dev->info = &spear_adc_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = spear_adc_iio_channels;
+ indio_dev->num_channels = ARRAY_SIZE(spear_adc_iio_channels);
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto errout2;
+
+ dev_info(dev, "SPEAR ADC driver loaded, IRQ %d\n", irq);
+
+ return 0;
+
+errout2:
+ clk_disable_unprepare(st->clk);
+ return ret;
+}
+
+static int spear_adc_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct spear_adc_state *st = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ clk_disable_unprepare(st->clk);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id spear_adc_dt_ids[] = {
+ { .compatible = "st,spear600-adc", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, spear_adc_dt_ids);
+#endif
+
+static struct platform_driver spear_adc_driver = {
+ .probe = spear_adc_probe,
+ .remove = spear_adc_remove,
+ .driver = {
+ .name = SPEAR_ADC_MOD_NAME,
+ .of_match_table = of_match_ptr(spear_adc_dt_ids),
+ },
+};
+
+module_platform_driver(spear_adc_driver);
+
+MODULE_AUTHOR("Stefan Roese <sr@denx.de>");
+MODULE_DESCRIPTION("SPEAr ADC driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/iio/adc/stx104.c b/drivers/iio/adc/stx104.c
index be2de48844bc..2df84fa5e3fc 100644
--- a/drivers/iio/adc/stx104.c
+++ b/drivers/iio/adc/stx104.c
@@ -318,6 +318,7 @@ static int stx104_probe(struct device *dev, unsigned int id)
}
indio_dev->name = dev_name(dev);
+ indio_dev->dev.parent = dev;
priv = iio_priv(indio_dev);
priv->base = base[id];